Which family on the periodic table is generally the most reactive (readily loses one electron to form a $M^{+}$ ion)?

• A. Noble gases (Group 18)
• B. Alkali metals (Group 1)
• C. Transition metals (Groups 3–12)
• D. Alkaline earth metals (Group 2)

Answer: (B)

Verified step by step guidance

1. Identify the characteristic of the ion formed: the problem states the element readily loses one electron to form an M⁺ ion, which means it forms a +1 charge by losing a single electron.
2. Recall the general properties of the groups: Alkali metals (Group 1) have one electron in their outermost shell, making it easy to lose that electron and form a +1 ion.
3. Compare reactivity trends: Alkali metals are known to be highly reactive because they have low ionization energies, meaning they lose their outer electron very easily compared to other groups.
4. Consider other groups: Noble gases (Group 18) are generally unreactive because they have full outer shells; alkaline earth metals (Group 2) lose two electrons to form +2 ions; transition metals (Groups 3–12) can lose varying numbers of electrons but are less reactive than alkali metals in losing just one electron.
5. Conclude that the family most reactive in losing one electron to form an M⁺ ion is the Alkali metals (Group 1) due to their single valence electron and low ionization energy.